DIRECT TO HOME (DTH)

DTH is a new technology and it has matured to its full potential in other parts of the world. There are many application has been found everyday for exploitation of benefits of DTH?

The word ‘DTH’ is synonymous with transmission of digital video channel to home subscriber’s using a small dish antenna. The DTH utilizes a technology which enables a home to receive high speed internet broadband access data communication, voice over internet protocol (IP) telephony and much more using an open standard Digital Video Broadcasting (DVB) technology. The video channels are received with a suitable set top box. Capable of demodulating Motion Picture Engineering Group (MPEG-2) standard videos. It is for the return channel required for other services such as voice over internet protocol and broadband access data communications, that a return channel is also required for the home terminal. The return channel via the satellite is called RCS and is an open standard.

Hardware compatible with DVB-RCS technology are readily available in the market in both Ku-band and C-band. DVB-RCS is an international open standard for multimedia satellite network where the return data rates in access of 2 Mbps are possible using low cost user terminals. The forward ink is usually at 40 Mbps.

 Today, most satellite TV customers in developed television markets get their programming        through a direct broadcast satellite (DBS) provider, such as DISH TV or DTH platform. The provider selects programs and broadcasts them to subscribers as a set package. Basically, the provider’s goal is to bring dozens or even hundreds of channels to the customer’s television in a form that approximates the competition from Cable TV. Unlike earlier programming, the provider’s broadcast is completely digital, which means it has high picture and stereo sound quality. Early satellite television was broadcast in C-band - radio in the 3.4-gigahertz (GHz) to 7-GHz frequency range. Digital broadcast satellite transmits programming in the Ku frequency range (10 GHz to 14 GHz). There are five major components involved in a direct to home (DTH) satellite

A PATH TOWARDS DTH

On June 25, 1967, for two hours 26 nations of the world were joined together by an invisible electromagnetic grid utilizing four satellites. The London-based production, in glorious black and white, was the first-ever use of satellites to simultaneously interconnect remote corners of the world to a single program event. The program, appropriately entitled "Our World," included the Beatles debuting the song "All You Need Is Love" to an audience estimated at more than 600 million.

During the course of the telecast, live feeds were interconnected through a pair of early design Intelsats, an American experimental satellite (ATS-1), and a Russian Molniya class bird. The New York Times would write about the ground-breaking telecast, "Our World was a compelling reaffirmation of the potential of the home screen to unify the peoples of the world."

Less than three decades later, or approximately the period of one generation of mankind, more than 30 million homes in the world are equipped with their own satellite dishes. The early Intelsat, ATS, and Molniya satellites were capable of relaying one (or at most, two) simultaneous TV programs; each satellite of the current generation easily can deliver as many as 200 program channels to dish antennas less than one-thirtieth of the size required for reception of the original "Our World" telecast.

Well before the turn of the century, virtually any location in Asia or the Pacific will have direct access to hundreds of channels of TV, high-speed Internet links, and thousands of radio program channels. It is not an exaggeration to suggest that satellites are redesigning the very fabric of life by creating full-time universal access to "our world."

All of this technology creates virtually unlimited opportunities for new business enterprise and personal development. You are holding in your hand a key that will unlock for you, your family, and your business the "secrets" of the 21st century "Information Revolution." There has never been a point in the history of the world when so much opportunity has presented itself to mankind. Use what you learn here wisely and your life will forever be changed.

The DTH

DTH stands for Direct-To-Home television. DTH is defined as the reception of satellite programmes with a personal dish in an individual home.

DTH does away with the need for the local cable operator and puts the broadcaster directly in touch with the consumer. Only cable operators can receive satellite programmes and they then distribute them to individual homes.

Working of DTH

A DTH network consists of a broadcasting centre, satellites, encoders, multiplexers, modulators and DTH receivers.

A DTH service provider has to lease Ku-band transponders from the satellite. The encoder converts the audio, video and data signals into the digital format and the multiplexer mixes these signals. At the user end, there will be a small dish antenna and set-top boxes to decode and view numerous channels. On the user's end, receiving dishes can be as small as 45 cm in diameter.

DTH is an encrypted transmission that travels to the consumer directly through a satellite. DTH transmission is received directly by the consumer at his end through the small dish antenna. A settop box, unlike the regular cable connection, decodes the encrypted transmission.

HOW DOES DTH REALLY DIFFER FROM CABLE TV?

The way DTH reaches a consumer's home is different from the way cable TV does. In DTH, TV channels would be transmitted from the satellite to a small dish antenna mounted on the window or rooftop of the subscriber's home. So the broadcaster directly connects to the user. The middlemen like local cable operators are not there in the picture.

DTH can also reach the remotest of areas since it does away with the intermediate step of a cable operator and the wires (cables) that come from the cable operator to your house. As we explained above, in DTH signals directly come from the satellite to your DTH dish.

Also, with DTH, a user can scan nearly 700 channels!

DTH RATHER THAN CABLE TV

DTH offers better quality picture than cable TV. This is because cable TV in India is analog. Despite digital transmission and reception, the cable transmission is still analog. DTH offers stereophonic sound effects. It can also reach remote areas where terrestrial transmission and cable TV have failed to penetrate.

Apart from enhanced picture quality, DTH has also allows for interactive TV services such as movie-on-demand, Internet access, video conferencing and e-mail. But the thing that DTH has going for it is that the powerful broadcasting companies like Star, Zee, etc are pushing for it.

In DTH, the payments will be made directly by the subscriber to the satellite company offering the service.

A big problem that broadcasters face in India is the issue of underreporting of subscribers by cable operators.

Consider the cable operators pyramid. Right at the top is the broadcaster. Next comes the Multi Service Cable Operator (MSOs) like Siticable, InCable, etc. Below them are the Access Cable Operators (ACOs) or your local cable guy who actually lays the wires to your house.

The local cable operators or the ACOs then allegedly under-report the number of subscribers they have bagged because they have to pay the MSOs something like Rs 30-45 per household. Showing a lesser number of households benefits ACOs.

With no way to actually cross check, the MSOs and the broadcasters lose a lot. Broadcasters do not earn much in subscription fees and are mostly dependent on advertisement revenue to cover their costs, which is not sustainable and does not

offer high growth in revenues for broadcasters.

The way out of this is to use a set-top box so that it will be clear how many households are actually using cable or going for DTH where broadcasters directly connect to consumers and can actually grow revenues with a growth in the subscriber base.

Today, broadcasters believe that the market is ripe for DTH. The prices of the dish and the set-top box have come down significantly. Overall investments required in putting up a DTH infrastructure has dropped and customers are also reaping the benefits of more attractive tariffs.

The major thing that DTH operators are betting on is that the service is coming at a time when the government is pushing for CAS (conditional access system), which will make cable television more expensive, narrowing the tariff gap between DTH and cable.

WILL DTH BE CHEAPER THAN CABLE OR MORE EXPENSIVE?

DTH will be definitely more expensive than cable as it exists today.

A set-top box is a must for DTH. Earlier, when CAS made set-top box mandatory for households, the costs between DTH and cable would not have been too wide.

But CAS on the backburner now -- which means no set-top box (a must for DTH), the price gap between DTH and cable, will be wide.

In Oct 2002, Siticable, which is owned by Zee, said that the cost of the installation equipment, which includes the receiver dish and the set-top box, would be priced at around Rs 3,900. Siticable is looking to rope in 1 million subscribers in 15 months.

Other estimates say that digital cable set-top box may cost Rs 4,000, a DTH decoder dish is unlikely to cost less than Rs 7,000.

 DTH's minimum subscription could be priced around Rs 500 per month.

Some reports say that an entry level DTH STB will cost about Rs 7,000 (including taxes and installation cost at consumers end). A more advanced STB with value added features like PVR (Personal Video Recorder), PSTN connectivity, Gamming console, channel management system, etc. may cost as much as Rs 15,000.

HISTORY OF DTH IN INDIA

DTH services were first proposed in India in 1996. But they did not pass approval because there were concerns over national security and a cultural invasion. In 1997, the government even imposed a ban when the Rupert Murdoch-owned Indian Sky Broadcasting (ISkyB) was about to launch its DTH services in

India.

Finally in 2000, DTH was allowed. The new policy requires all operators to set up earth stations in India within 12 months of getting a license. DTH licenses in India will cost $2.14 million and will be valid for 10 years. The companies offering DTH service will have to have an Indian chief and foreign equity has been capped at 49 per cent. There is no limit on the number of companies that can apply for the DTH license.

MARKET COMPARISON OF DTH AND CABLE TV

The cable system is well entrenched in India and is showing quite rapid growth. If DTH had come to India in 1996-97 (like Star had originally attempted), then it could have made a significant breakthrough.

Europe is an example of this. DTH developed there before cable and now controls nearly 80 per cent of the total satellite television subscriber base. But in US, cable rules because it came before DTH.

DTH will definitely cut into the existing cable user base. It will make the local cable operator less important and take business away from him. It will give consumers greater choice.

But it is likely to be an up market premium product and most middle class households will stick to cable.

OVERVIEW OF DTH SYSTEMS

Direct to Home are nothing but the Direct Broadcast Satellite Television and Radio Systems. Geostationary satellites play an important role for DTH systems. In general, DTH service is the one in which a large number of channels are digitally compressed, encrypted and beamed from very high power Geostationary satellites. The programs can be directly received at homes. Also, DTH transmission eliminates local cable operator completely, since an individual user is directly connected to the service providers.

An individual user has a small dish usually 45 to 60cm in diameter and Low Noise Block Converter (LNBC) pointed towards satellite. At home digital receiver i.e. Set top box is connected to TV which receives digitally multiplexed channels from LNBC and gives RF output for TV.

The satellite transmission is usually in Ku-Band. The digital channels are first multiplexed and then QPSK modulated before transmission. The small dish along with LNBC receives the signals and LNBC converts these Ku band signals to Intermediate Frequency based on the local IF which is typically 10.7GHz. Now, the set top box receives the down-converted satellite signals and performs the demodulation and de-multiplexing and finally D to A conversion before making signal competent to TV.

The DTH receivers available in the Market are affordable and the use of such systems is nowadays increasing dramatically in urban as well as ruler areas.

CONCLUSION

DTH projects in India are just a beginning and we are taking the advantage of DTH revolution. Direct to home connects urban, rural and remote areas of the country and provides desire information communication, education and entertainment at the click of a button.

1.      Broadband noise will have negligible effect on GMRT Observations, as the minimum separation distance is 90 meters with the assumption that there is no DTH system in 100 meter circle from any of the GMRT antennas. Care must be taken for arm antennas.

2.      Narrow band noise can cause RFI, in spectral line observations below 400MHz, if located at about 2 km from a GMRT antenna.